Re: [PATCH v4 2/3] phy: qcom: qmp-combo: get the USB3 & DisplayPort lanes mapping from DT

From: Neil Armstrong
Date: Wed Oct 01 2025 - 03:06:27 EST


On 9/30/25 20:56, Dmitry Baryshkov wrote:
On Tue, Sep 30, 2025 at 09:39:48AM +0200, Neil Armstrong wrote:
The QMP USB3/DP Combo PHY hosts an USB3 phy and a DP PHY on top
of a combo glue to route either lanes to the 4 shared physical lanes.

The routing of the lanes can be:
- 2 DP + 2 USB3
- 4 DP
- 2 USB3

Get the lanes mapping from DT and stop registering the USB-C
muxes in favor of a static mode and orientation detemined
by the lanes mapping.

This allows supporting boards with direct connection of USB3 and
DisplayPort lanes to the QMP Combo PHY lanes, not using the
USB-C Altmode feature.

Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
---
drivers/phy/qualcomm/phy-qcom-qmp-combo.c | 145 ++++++++++++++++++++++++++++--
1 file changed, 137 insertions(+), 8 deletions(-)

@@ -4167,9 +4269,41 @@ static int qmp_combo_probe(struct platform_device *pdev)
if (ret)
goto err_node_put;
- ret = qmp_combo_typec_register(qmp);
- if (ret)
- goto err_node_put;
+ qmp->qmpphy_mode = QMPPHY_MODE_USB3DP;
+
+ if (of_find_property(dev->of_node, "mode-switch", NULL) ||
+ of_find_property(dev->of_node, "orientation-switch", NULL)) {
+ ret = qmp_combo_typec_register(qmp);
+ if (ret)
+ goto err_node_put;
+ } else {
+ enum typec_orientation dp_orientation = TYPEC_ORIENTATION_NONE;
+ enum typec_orientation usb3_orientation = TYPEC_ORIENTATION_NONE;
+
+ ret = qmp_combo_get_dt_dp_orientation(dev, &dp_orientation);
+ if (ret)
+ goto err_node_put;
+
+ ret = qmp_combo_get_dt_usb3_orientation(dev, &usb3_orientation);
+ if (ret)
+ goto err_node_put;
+
+ if (dp_orientation == TYPEC_ORIENTATION_NONE &&
+ usb3_orientation != TYPEC_ORIENTATION_NONE) {
+ qmp->qmpphy_mode = QMPPHY_MODE_USB3_ONLY;
+ qmp->orientation = usb3_orientation;
+ } else if (usb3_orientation == TYPEC_ORIENTATION_NONE &&
+ dp_orientation != TYPEC_ORIENTATION_NONE) {
+ qmp->qmpphy_mode = QMPPHY_MODE_DP_ONLY;
+ qmp->orientation = dp_orientation;
+ } else if (dp_orientation != TYPEC_ORIENTATION_NONE &&
+ dp_orientation == usb3_orientation) {
+ qmp->qmpphy_mode = QMPPHY_MODE_USB3DP;
+ qmp->orientation = dp_orientation;
+ } else {
+ dev_warn(dev, "unable to determine orientation & mode from data-lanes");
+ }
+ }
ret = drm_aux_bridge_register(dev);
if (ret)
@@ -4189,11 +4323,6 @@ static int qmp_combo_probe(struct platform_device *pdev)
if (ret)
goto err_node_put;
- /*
- * The hw default is USB3_ONLY, but USB3+DP mode lets us more easily
- * check both sub-blocks' init tables for blunders at probe time.
- */
- qmp->qmpphy_mode = QMPPHY_MODE_USB3DP;

SHouldn't this still be a default in the 'normal' USB-C case?

It is, I just moved it before the added logic, but the comment doesn't really
apply anymore

Neil


qmp->usb_phy = devm_phy_create(dev, usb_np, &qmp_combo_usb_phy_ops);
if (IS_ERR(qmp->usb_phy)) {

--
2.34.1